/Engine/Source/Runtime/GeometryCore/Public/Generators/MarchingCubes.h
Below here are standard marching-cubes tables.
static constexpr int EdgeIndices = { {0,1}, {1,2}, {2,3}, {3,0}, {4,5}, {5,6}, {6,7}, {7,4}, {0,4}, {1,5}, {2,6}, {3,7} };